Semiconductor dice and their interconnections are sealed within a package of plastic or other moldable material (e.g., thermosetting resin) to protect the semiconductor dice and their interconnections from physical and/or environmental stresses (e.g., dust, heat, moisture, static electricity, and/or mechanical shocks). The plastic or other moldable material (e.g., liquefied) is fed into cavities of a mold (e.g., formed between the upper part of the mold and the substrate surface of the semiconductor dice) to fill the cavities, thus flowing over the semiconductor dice and their interconnections.
The plastic or moldable material is then hardened to encapsulate the semiconductor dice and their interconnections. Air formed during the molding process is expelled through one or more airvents formed on the substrate surface. Through the one or more airvents, the plastic or moldable material could flow outside the cavities, thus resulting in mold bleeding. The mold bleeding may be worsened when outer edges of the substrate surface (e.g., surrounding the cavities) use an aligned mesh block design (e.g., of FWD 137 package, BNA 202, etc.) to achieve a better warpage performance. The aligned mesh block design may create a drainage flow from the cavities, thus aggravating the mold bleeding on the edges of the substrate surface. Furthermore, the mold bleeding may also result when a gap between two adjacent areas of the aligned mesh block design is too wide.
As a result, the mold bleeding may decrease the quality of the package and/or degrade equipment used to encapsulate the semiconductor dice and their interconnections. Additionally, a subsequent process may be necessary to remove the mold bleeding (e.g., for aesthetic reason) from the substrate surface and/or the equipment. For these reasons or more, the mold bleeding may lead to low yield and/or low productivity in semiconductor manufacturing and/or process control.